This invention relates generally to magazines which can be pre-loaded with a quantity of objects and then used for repeatedly dispensing those objects. More particularly, the invention relates to a magazine for controllably dispensing a large quantity of objects which are elongate and generally cylindrical in shape as well as a method for pre-loading and dispensing such objects.
One common use of such a magazine is in connection with apparatus which perform automated instrumental analysis on various types of samples contained in cylindrical cartridges. For example, the apparatus disclosed in the co-pending U.S. patent application Ser. No. 663,095, filed Oct. 19, 1984, and commonly assigned herewith is capable of analyzing a series of individual biological samples in syringe-like cartridges. This analysis is performed in a cycle involving several steps performed on each sample cartridge such as the introduction of various reagents, incubation, optical assay, etc. The process is made fully automatic and capable of continuous operation because it loads each sample cartridge into a continually rotating wheel which transports it to the different operating stations. The rotation of the wheel and the position of the stations around the wheel are selected so as to provide the proper timing and duration of each step to be performed.
This particular mode of operation requires a source of sample cartridges which can deliver individual cartridges to the analyzing apparatus in a highly reliable manner. Naturally, it would be inconsistent with the object of providing for long periods of unattended performance to rely on manual input of each sample cartridge into the analyzing apparatus when required. Rather, a better system for supplying the sample cartridges would be one that could be pre-loaded with a large quantity of sample cartridges and then automatically dispense those cartridges when needed.
Although the sample cartridges used in the above apparatus are elongate and generally cylindrical, there are certain irregularities in their shape. Unfortunately, these irregularities present various problems in handling the cartridges which make otherwise simple loading methods or apparatus unworkable. For example, the gripping flange which protrudes from the barrel of the syringe keeps the cartridge from rolling in a straight line, thus complicating the use of gravity feed or stacking arrangements.
Further requirements are imposed on this type of magazine when it is used in connection with this automated analyzer. The magazine will have size constraints dictated by the analyzer. That is, the magazine must be made to fit in the analyzer. Also, to allow the analyzer to run for long periods without intervention, it will be desirable for the magazine to handle large numbers of cartridges. Additionally, in order to increase convenience in loading the magazine, it would be desireable to provide a magazine which can be readily detached and reattached to the analyzer and easily carried so that it can be loaded at a work station remote from the analyzer.
In addition to this specific analyzer, there exist other analytical and manufacturing applications which involve these same problems of handling elongate and generally cylindrical objects. It is likely that many of these applications would be benefited by an improved magazine which could be pre-loaded and then controllably and reliably dispense those objects on demand.